(a) Technical Field
The present disclosure relates to a variable compression ratio engine, and more particularly, to a variable compression ratio engine in which a compression ratio varies and cylinder deactivation is enabled.
(b) Description of the Related Art
In general, a compression ratio of an internal combustion engine refers to a ratio between a maximum volume before compression in a combustion chamber and a minimum volume after compression in the combustion chamber during a compression stroke of the internal combustion engine.
An output of the internal combustion engine is increased as the compression ratio of the internal combustion engine is increased. However, if the compression ratio of the internal combustion engine is too high, a so-called knocking phenomenon occurs, and as a result, an output of the internal combustion engine deteriorates, and overheating of the internal combustion engine, a breakdown of a valve or a piston of the internal combustion engine, and the like are caused. Therefore, the compression ratio of the internal combustion engine is set to a particular value within an appropriate range before the knocking phenomenon occurs.
However, various methods of varying the compression ratio of the internal combustion engine have been proposed because fuel economy and an output of the internal combustion engine may be improved by appropriately changing the compression ratio in accordance with a load of the internal combustion engine.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.